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Flexible cooling device made by UCLA engineers. Photo: UCLA Engineering

Researchers from UCLA and SRI International have developed a flexible, lightweight, cooling system that — if it can be mass-produced cost-effectively —could become a competitive cooling technology for small devices.

The problem: Vapor compression cooling systems used in air conditioners, cars and refrigerators are too large and bulky for much smaller applications like keeping smartphone batteries cool. Ceramic materials can be used but so far have been costly and less efficient than conventional cooling systems.

What they did: The researchers layered thin films of a polymer between two aluminum plates — one that was the source of heat (representing a smartphone battery, for example) and one that absorbed heat. As they applied and removed an electric field over the films, the polymer acts as the refrigerant — and moves heat back and forth between the plates. Repeating that process, they were able to cool a smartphone battery by more than 14 degrees Fahrenheit in 5 seconds.

Go deeper

Biden extends mask mandates for travelers into 2022

President Biden delivers remarks at the White House on Dec. 1. Photo: Anna Moneymaker via Getty Images

President Biden will announce new testing protocols for international travelers on Thursday and extend masking requirements through March as the U.S. prepares to fight the Omicron variant this winter, according to senior administration officials.

Driving the news: The U.S. will tighten pre-departure testing protocols starting early next week by requiring all inbound international travelers to take COVID-19 tests within one day of their departure rather than three.

53 mins ago - Health

America probably won't lead the effort to understand Omicron

Illustration: Eniola Odetunde/Axios

The race to figure out just how dangerous the Omicron variant is will likely be a global effort, but some experts are skeptical that the U.S. will play a dominant role.

Why it matters: The CDC has repeatedly come under fire for inadequate data collection throughout the pandemic — and figuring out how to respond to Omicron requires a lot of data that doesn't currently exist.

U.S. faces urgent anti-hacker crisis

Illustration: Allie Carl/Axios

The Biden administration is accelerating efforts to fill nearly 600,000 vacant cybersecurity positions in the public and private sectors bogging down efforts to protect digital infrastructure.

Why it matters: Following a deluge of ransomware attacks targeting critical government and corporate infrastructure this year, clogs in the talent pipeline are leaving federal, cash-strapped local governments and Big Business even more susceptible to hacking.